" To one gallon of 90 or 95 per cent alcohol, add one quart of refined turpentine or camphene, and half an ounce of pulverized gum camphor, and to the above add four grains of sulphuric ether ; shake or stir the whole together, and let it remain from 15 to 18 days, occasionally shaking it to unite the ingredients. Then, if the composition is not transparent, you must add a sufficient quantity of alcohol, to bring it to the natural color of the alcohol before it was mixed ; then it is ready for use. Trim your lamps, put your tubes in the lamps well filled with cot-ton-wicking, and your lamps will burn clear without affecting the wick, and give a brilliant light, free from smoke or smell. The above is called ' Foster's Patent Chemical Burning Composition.' " A correspondent in Spring Valley, Rockland county, N. Y., sends us the above, stating that it has been sold by an agent to a great number of persons in that section of country, upon the assurance that it is superior for cleanliness, cheapness, and for giving a brilliant light, to all other burning fluids, mixtures or compositions now known ; also that " it will not explode if exposed to fire, in any way it may be placed." Our opinion is solicited regarding its explosive character. It is, no doubt, a very good burning fluid, but no better nor cheaper than that made of super-refined turpentine and 95 per cent proof alcohol alone. None of the volatile burning fluids, so called, are explosive in the fluid state, and the agent referred to may have told the truth, but in such a way as to delude the purchasers of his recipe. All volatile fluids are dangerous, because of their liability to assume the gaseous form, mix with the atmosphere, and then become explosive when ignited. The above burning fluid is as dangerous to use as any of the burning fluids which are understood to be explosive, because it is just as volatile.